Air conditioning apparatus



April 9, 1963 M. e. MILLSPAUGH AIR connmcumc APPARATUS 2 Sheets-Sheet 1 Filed July 28, 1955 INVENTOR.

MARION G- MILLSPAUGH BY April 9, 1963 M. G. MILLSPAUGH 3,084,741.

AIR CONDITIONING APPARATUS Filed July 28, 1955 2 Sheets-Sheet 2 INVENTOR.

MARION G. MILLSPAUGH 3,084,741 Patented Apr. 9, 1963 ice 3,0fi4fl41 AIR CONDITIONING APPARATUS Marion G. Millspaugh, Ellrhart, Ind. Filed July 28, 1955, Ser. No. 524,838 4 Claims. ((11. 165-2t'i) The present invention relates to air conditioning apparatus and more particularly to apparatus for maintaining a uniform room temperature by electrically heating or cooling the air.

It is one of the principal objects of the present invention to provide an apparatus for maintaining a predetermined temperature in a room or the like wherein the operating capacity of said apparatus is varied in accordance with variations in the outdoor temperatures.

Another object of the present invention is to provide an air conditioning apparatus wherein the air is filtered, sterilized and then heated or cooled to give a preselected room temperature.

Another object of the invention is to provide an air heating apparatus having a plurality of electrical elements wherein the number of said elements in operation during the heating cycle is determined by the outdoor temperature.

Still another object of the invention is to provide an air conditioning apparatus wherein the input for a given period of time during either a heating or cooling cycle is varied in accordance with the outdoor temperature.

A further object of the invention is to provide an air conditioning unit which increases or decreases the number of effective heat exchangers as the outdoor temperature reaches certain preselected temperatures.

Another object of the invention is to provide a method of treating or conditioning air wherein the air is heated and/or cooled electrically to give a preselected temperature, in such a manner as to give maximum power input economy.

Additional objects and advantages will become apparent from the following description read in connection with the accompanying drawings, wherein:

FIGURE -1 is a front elevational view of my air conditioning unit, from which the panels have been removed to show the various components in operative relation to one another;

FIGURE 2 is a side elevational view of my apparatus from which the panel has been removed to further show the relationship of the various components; and

7 FIGURE 3 is a wiring diagram of the electrical control circuitry of the air conditioning apparatus.

Referring more specifically to the drawings and to FIGURE 1 in particular, my air conditioning apparatus from which the front panels have been removed consists generally in a housing 10 having a compartment 12, for a filter 14, ultra-violet lights 16 and a blower 18 and a compartment 20 for heating elements 22 and cooling coils 24 and 25. The air is drawn from the space to be heated or cooled and/or from the outside through one or more ducts 26 and bonnet 28 mounted above and communicating with compartment 12. The air on passing through the two compartments leaves the apparatus through a bonnet 30 and one or more ducts 31 leading to the space being heated or cooled. The controls in the apparatus are housed generally in control box 32 in the bottom of compartment 20.

The filter element 14 can be of any suitable material such as fiberglass, metal, wool or the like disposed in frame 33 through which air will flow with little or no resistance. The frame is supported on brackets 36 and 38 on the sidewalls of compartment 12 anterior to the blower and can be readily removed from the apparatus for cleaning. Beneath the filter are two germicidal lamps 16 not shown or described in detail herein.

supported at one end by electrical fixtures 40 and 42 and at the other end by a corresponding pair of fixtures (not shown). These lamps are connected in the electric circuit for the blower motor and controlled by thecontrol elements of said motor and are therefore in operation whenever air is flowing through the apparatus in substantial volume.

The air is drawn through air inlet ducts 26 and bonnet 28 into compartment 12 by a blower 18 which may be any well known type and is forced by said blower through duct 44 into compartment 20 past heating elements 22. A multiple-speed motor 45 is preferably used to drive the blower to provide the correct volume of air for any particular number of heating elements in operation at any given time. On entering compartment 20 the air is directed by a plurality of bafiies 46 to and around the heating elements and thence upwardly toward the cooling coils and air outlet bonnet 30.

The electrical heating elements 22, which may be any one of the well known types such as a Calrod unit or a coil resistance wire mounted on an insulating core, are supported in spaced relation in the lower part of compartment 20 on fixtures '50 and 52 resting on the floor of the apparatus. The elements shown consist of straight Calrod elements having numerous equally spaced radial fins 53 secured to the protective outer tube of the rod and are connected into the electrical circuit in banks 54, 56 and 58 of three elements each. The number of banks and the number of elements per bank may vary from one installation to another. In the operation of the heating unit one or more of the banks are used; for example, bank 54 alone may be used during mildly cool weather, banks 54 and 56 may be used during moderately cold weather and all three banks are used during extremely cold weather. By varying the number of operative banks in accordance with the outside temperature a considerable saving in power consumption is obtained, While the elements of one bankare shown in the drawings arranged alternately with the elements of the other banks, other arrangements are possible, as for example the elements of each bank may be grouped together. A diiferent number of elements in each bank and a different number of banks than those shown may be successfully used.

Cooling coils '24 and 25 which are mounted above the heating elements in compartment 20 are part of refrigcrating systems consisting of the usual electrically driven compressor, condensing coils and cooling unit, which, for the purpose of the present invention, may be considered conventional in design and construction and therefore are The cooling coils are in two separate banks disposed at an angle and are spaced from one another at the top to provide an air flow passage 64 for the air to by-pass the cooling coils when the heating elements are in operation. This passage is controlled by a damper 66 operated by a solenoid or electrical motor in housing 68 and is closed thereby when the cooling system is in operation. Drip troughs 70 connected with a collector channel 72 and drain tube 74 are provided beneath the coils to catch the condensed moisture as it drips from the coils. Separate refrigerating units are preferably employed for each bank of cooling coils so that one bank can be used for moderately warm weather and both banks can be used for hot weather, thusproviding considerable savings in power input during mild weather. When only one bank, for example bank 24, is in operation, damper 66 is closed causing the air to pass through both coils 24 and 25. The air passing through bank 24 is cooled and thereafter circula-ted and mixed with the uncooled air passing through bank 25 to give the moderate cooling effect required. During hot weather both banks are in operation so that all the air passing through compartment is cooled. In place of having the cooling coils in two separate banks, the coils of the two banks can be divided into sections and disposed on both sides of compartment 20 so that all the air will be moderately cooled when only one bank is in operation. While two banks are shown, only one with one refrigerating unit or more than two banks with a corresponding number of refrigerating units may be used. If only one bank is used it can be divided into two sections to occupy the positions shown for banks 24 and 25. Even if only one refrigerating unit is used, multiple level cooling can still be accomplished by using a valve, such as a solenoid valve, responsive to an outdoor thermostatic switch, to render one bank of cooling coils inoperable for moderately warm weather. The valve is opened during hot weather, permitting both banks to operate.

The circuitry for controlling the operation of my air conditioning apparatus is shown in FIGURE 3. Bank 54 of heating elements which are in operation alone during mild weather is controlled by a low voltage circuit consisting of leads and 92 from the power supply, room thermostatic switch 94, contact 95, lead 96 connecting the thermostat to a limit switch 98 on bonnet 30, leads 100 and 102 connecting the limit switch with a relay 104 for operating switch 106 and lead 107 connecting the relay with the power supply. Switch 106 controls the circuit to heating element bank 54 from the main power supply consisting of lead 108 to switch 106 and lead 110 connecting the switch with bank 54 and lead 112 connecting said bank with the power supply. When thermostatic switch 94 closes, relay 104 is energized thus completing the circuit for the heating elements of bank 54. The bank 56 which comes into operation along with bank 54 for moderately cold weather is controlled by a circuit consisting of leads '90 and 92, thermostatic switch 94, lead 96, limit switch 98, leads 100 and 114 and relay 116 which operates switch 118. Lead 120 connects relay 116 to a thermostatic switch 122 which is located outof-doors and is set to close when the temperature decreases to 40 degrees F. for example. Leads 123 and 10 7 connect switch 122 with the power supply. Switch 118 controls the circuit to the elements of bank 56, consisting of leads 108, 124, 125 and 112. Bank 58 which comes into operation along with banks 54 and 56 for cold weather is controlled by a circuit consisting of leads 90 and 92, thermostatic switch 94, lead 96, limit switch 98, leads 100 and 126 and relay 130 which operates switch 134. The relay is connected by lead 136 to therrnostatic switch 138 which is also located out-of-doors and is set to close when the temperature decreases for example to 20 degrees F. This latter switch is connected to the power supply by leads 140 and 10-7. Switch 134 controls the circuit to the elements of bank 58 consisting of leads 108, 142, 144 and 112.

The circuit for a two-speed blower motor consists of lead :from the power supply to switch 152, leads 154 and 156 connecting the switch and the motor, and lead 158 connecting the motor with the power supply. Switch 152 is controlled for low speed by a circuit consisting of leads 90 and 160, thermostatic switch 162, lead 164, relay 166 and leads 168 and 107, thermostatic switch 162 I being located in bonnet 30 to turn on the motor when a predetermined temperature is reached therein. Switch 152 is controlled for high speed by a circuit consisting of leads 90 and 160, thermostatic switch 162, leads 164 and 170, relay 172, leads 174 and 120, thermostatic switch .122 and leads 123 and 10 7. A switch 176 is placed in lead 168 and is operated by a relay 180 connected in parallel with relay 172 for interrupting the circuit to relay 166 when relay 172 is energized.

Germicidal lamps 16 are connected into the blower motor circuit by leads 18 8 and and are controlled ,tion.

4 by the switch 152 so that they operate simultaneously with the motor.

The refrigerating units for cooling coils 24 and 25 are shown diagrammatically at numerals 198 and 200 respectively. Unit 19 8 is controlled by thermostat 94 through a circuit consisting of contact 201, lead 202, relay 204, and leads 206 and 107. Relay 204 operates a switch 208 in the units power supply circuit. The blower mo tor and a solenoid 209 for closing damper 66 are controlled simultaneously with refrigerating unit 198 by a circuit consisting of lead 210 connected with lead 160 and lead 212 connected with lead 164 for the motor, and lead 213 connected with lead 212 and lead 214 connected with lead 107. A switch 215 in said circuit operated by a relay 216 which is energized by leads 218 and 220 synchronizes the operation of the blower motor with the refrigerating unit. Unit 200 is cont-rolled by thermostat 94 and thermostatic switch 222 which is located out-ofdoors, through a circuit consisting of contact 201, leads 202 and 224, relay 226, lead .228 connecting said relay to thermostat 222 and lead 230' connecting said switch with lead 107. Relay 226 operates switch 232 which controls the main power supply circuit for unit 200.

V In the operation of the present air conditioning apparatus when the outdoor temperature is. mild, closing of the thermostatic switch 94 at contact 95 places the elements of bank 54- in operation and also switches the motor on at slow speed as soon as the temperature around thermostatic switch 162 in bonnet 30 is high enough to close said switch. When the circuit to the motor is closed the germicidal lamps are energized and remain in operation until the motor circuit is interrupted. 'If the outdoor temperature decreases below 40 degrees F. the elements of bank 56 are placed in operation along with those of bank 54 and the motor is switched on at high speed. If the outdoor temperature decreases below 20 degrees F. the elements of bank 58 are placed in opera- During the operation of the foregoing units the air is drawn by blower 18 into compartment 12 through filter 14 around germicidal lamps 16, through the blower into compartment 20, around the heating elements 22- and thence pastthe open damper and out through bonnet 30. When the air in the space being heated reaches the ,response to decreased air temperatures in bonnet 28, .opens.

,, If in warm weather the temperature of the space rises to a predetermined degree as established by the setting on thermostatic switch 94, said switch closes at contact 201 energizing the air conditioning unit 198, closing damper 66, starting the blower motor 45, and energizing the germicidal lamps 16. These units continue to operate as long as necessary to maintain the desired temperature as indicated by the thermostatic switch 94. If

. the outdoor temperature rises above a 90 degree setting on thermostat 222, for example, unit 200 comes into operation to assist unit 198 so long as the temperature remains above said setting.

Various modifications may be made in the air conditioning apparatus disclosed herein, either adding features or omitting some of the features described, without departing from the scope of the present invention.

I claim:

1. An air conditioning apparatus for buildings and similar structures, comprising a housing having an air passage therein, an air filter in said passage, a means for sterilizing the air passing through said passage, an air blower, a multiple speed motor for driving said blower, a plurality of elements for heating the air passing through said passage, a circuit for controlling said blower motor and said elements having a switch responsive to the temperature in the building or other structure for placing one or more of said elements in operation, thermostatic switch for starting said motor after said elements start, and a switch responsive to the outdoor temperature for varying the number of efiective elements in operation and simultaneously varying the speed of said motor.

2. An air conditioning apparatus for buildings and similar structures, comprising a housing having an air passage therein, an air filter in said passage, a means for sterilizing the air passing through said passage, an air blower, a multiple speed motor for driving said blower, a plurality of means :for heating the air passing through said passage, a circuit for controlling said blower motor and said heating means having a switch responsive to the temperature in the building or other structure for placing one or more of said heating means in operation, thermostatic switch for starting said motor after said heating means start, and a switch adapted to close when the outdoor temperature decreases to a preselected degree for increasing the number of efiective heating means and simultaneously increasing the speed of said motor.

3. An air conditioning apparatus for buildings and similar structures, comprising a housing having an air passage therein, a blower in said passage, a multiple speed motor for driving said blower, a plurality of elements for heating the air passing through said passage, an air cooling means having a plurality of coils for cooling the air passing through said passage, a means forming a passage for by-pas-sing the air around said coils when one or more of said elements are in operation, a damper for closing said by-passage when said coils are in operation, an electrical means for operating said damper, a circuit for controlling said blower motor, elements and said cooling means having a switch adapted to close when the temperature in the structure decreases to a preselected degree for placing one or more elements in operation, switch means for starting said motor after said elements start, a switch adapted to close when the outdoor temperature decreases to a preselected degree for increasing the number of effective elements and simultaneously increasing the speed of said motor, a switch adapted to close when the temperature in said structure increases to a preselected degree for placing one of said cooling coils in operation, starting said motor and closing said damper, and a switch adapted to close when the outdoor temperature increases to a preselected degree -for increasing the 4 number of operative cooling coils.

4. An air conditioning apparatus for buildings and similar structures, comprising a housing having an air passage in which are disposed in series an air filter, a means for sterilizing the air passing through said passage, a blower, a multiple speed motor for driving said blower, a plurality of elements for heating the air passing through said passage, an air cooling means having coils for cooling the air passing through said passage, a means forming a passage for by-passing the air around said coils when one or more of said elements are in operation, a damper for closing said lay-passage when said coils are in operation, an electrical means -for operating said damper, a circuit for controlling said blower motor, elements, and said cooling means having a. switch adapted to close when the temperature in the structure decreases to a preselected degree for placing one or more elements in operation, switch means for starting said motor after said elements start, a switch adapted to close when the outdoor temperature decreases to a preselected degree for increasing the number of efi'ective elements and simultaneously increasing the speed of said motor, and a switch adapted to close when the temperature in said structure increases to a preselected degree for placing said cooling means in operation, starting said motor and closing said damper.

References Cited in the file of this patent UNITED STATES PATENTS 2,011,787 Whiteley Aug. 20, 1935 2,047,844 Wehner July 14, 1936 2,071,178 Roessler Feb. 16, 1937 2,091,563 Palmer Aug. 31, 1937 2,145,909 Zwickl Feb. 7, 1939 2,210,325 Newton Aug. 6, 1940 2,238,688 Guler Apr. 15, 1941 2,256,350 Nipt-rom Sept. 16, 1941 2,488,636 Mcndenhall et al Nov. 22, 1949 2,540,652 Cauchener Feb. 6, 1951 2,699,922; Herbst Jan. 18, 1955 2,783,975 Lans Mar. 5, 1957 2,806,674 Biehn Sept. 17, 1957 2,817,508 Swenzel Dec. 24, 1957 2,820,880 Huntsinger et al Jan. 21, 1958 FOREIGN PATENTS 363,370 Great Britain Dec. 10, 1931 

3. AN AIR CONDITIONING APPARATUS FOR BUILDINGS AND SIMILAR STRUCTURES, COMPRISING A HOUSING HAVING AN AIR PASSAGE THEREIN, A BLOWER IN SAID PASSAGE, A MULTIPLE SPEED MOTOR FOR DRIVING SAID BLOWER, A PLURALITY OF ELEMENTS FOR HEATING THE AIR PASSING THROUGH SAID PASSAGE, AN AIR COOLING MEANS HAVING A PLURALITY OF COILS FOR COOLING THE AIR PASSING THROUGH SAID PASSAGE, A MEANS FORMING A PASSAGE FOR BY-PASSING THE AIR AROUND SAID COILS WHEN ONE OR MORE OF SAID ELEMENTS ARE IN OPERATION, A DAMPER FOR CLOSING SAID BY-PASSAGE WHEN SAID COILS ARE IN OPERATION, AN ELECTRICAL MEANS FOR OPERATING SAID DAMPER, A CIRCUIT FOR CONTROLLING SAID BLOWER MOTOR, ELEMENTS AND SAID COOLING MEANS HAVING A SWITCH ADAPTED TO CLOSE WHEN THE TEMPERATURE IN THE STRUCTURE DECREASES TO A PRESELECTED DEGREE FOR PLACING ONE OR MORE ELEMENTS IN OPERATION, SWITCH MEANS FOR STARTING SAID MOTOR AFTER SAID ELEMENTS START, A SWITCH ADAPTED TO CLOSE WHEN THE OUTDOOR TEMPERATURE DECREASES TO A PRESELECTED DEGREE FOR INCREASING THE NUMBER OF EFFECTIVE ELEMENTS AND SIMULTANEOUSLY INCREASING THE SPEED OF SAID MOTOR, A SWITCH ADAPTED TO CLOSE WHEN THE TEMPERATURE IN SAID STRUCTURE INCREASES TO A PRESELECTED DEGREE FOR PLACING ONE OF SAID COOLING COILS IN OPERATION, STARTING SAID MOTOR AND CLOSING SAID DAMPER, AND A SWITCH ADAPTED TO CLOSE WHEN THE OUTDOOR TEMPERATURE INCREASES TO A PRESELECTED DEGREE FOR INCREASING THE NUMBER OF OPERATIVE COOLING COILS. 